oh, YES! I believe bat makes a huge difference. I use Hobbs 80/20 or their wool usually. I like that neither are very linty and have found that poly bats, especially if they are lofty or don't have any density to them, tend to pucker more. I am using a double bat of Hobbs 80/20 and Quilters Dream poly (could not find black wool anywhere) and like the Quilters Dream poly cause it is stable.